PITTSBURGH – The injuries to pitchers keep coming.

On Wednesday, the Pirates placed righthander Nick Burdi, once a highly regarded Twins prospect. on the 45-day injured list because of a right elbow issue. The Astros’ Justin Verlander is out indefinitely because of a forearm injury. Astros closer Roberto Osuna needs season-ending Tommy John surgery. The Angels’ Shohei Ohtani won’t pitch again this season because of an elbow issue. And so on.

The Twins have avoided any serious injuries to their pitchers so far, but they began an eight-game road trip Wednesday with three starters — lefthander Rich Hill and righthanders Homer Bailey and Jake Odorizzi — on the 10-day injured list.

The number of pitchers on the injured list, and a few with serious injuries, suggests something went wrong with how pitchers prepared during the shutdown and during summer camp.

“”I haven’t been able to draw any conclusions,” Twins pitching coach Wes Johnson said. “It’s more on an individual basis. You don’t know what a guy was doing during a quarantine. I think there are a lot of factors that could lead to the cause of some of that.

“Am I concerned? You probably have to say yes in some sense. But at the end of the day, we’re just trying to continue to get these guy stronger, continue to build them up and get them ready to compete.”

While spring training was halted in March, Johnson had his pitchers continue to build up, hoping for only a two-week delay. When it became evident the shutdown would be longer, Johnson had his starters throw a four-inning simulated game and his relievers throw a vigorous 20-30 pitch session each week, followed by light sessions.

“The challenge with all of that is as we all know, it’s not the same from an intensity level,” Johnson said. “There’s been studies on adrenaline and how much adrenaline and muscle capacity goes up and what it can take on. That’s something that’s really hard to replicate when you are throwing a [simulated] game and you are in an indoor facility or a wide-open park. I think that was some of the challenges that we’re running into.”

Slowly but surely, the Twins’ injured starters are closer to returning. Bailey, recovering from a sore biceps, can come off the IL on Saturday. Odorizzi, out because of lower back soreness, threw well in the bullpen Wednesday and could pitch during the weekend series at Kansas City. Hill hopes to throw a bullpen session by the end of the week and could be available during the series next week at Milwaukee.

Donaldson’s progress

Third baseman Josh Donaldson grabbed a glove and went to the field to take grounders. And he took a lot of them, but none were hit where he had to move to his right or left to get to them. Twins manager Rocco Baldelli walked over to third base to get a closer look at Donaldson’s work and the two chatted for a few minutes.

Donaldson eventually grabbed a bat and began to pummel batting practice pitches throughout PNC Park. He didn’t do any running, as he continues to recover from a tight right calf muscle. But the Twins brought him on the road trip, thinking he could return to the lineup soon.

“JD knows his body well enough to be able to lead us to a timeline,” Baldelli said. “We’re not gonna pretend to set a timeline for him. He understands what it takes to come back from these types of issues, so we’ll lean on him.”